聚苯胺的质子酸掺杂机制的研究

木文用FT-IR、ESR、XPS等研究了聚苯胺的质子酸掺杂机制。结果表明聚苯胺掺杂时的质子化反应优先发生在分子链中的醌亚胺结构单元的氮原子上,并产生了分子内氧化还原反应而形成阳离子自由基。质子所带的电荷由于共轭作用能较好地离域到邻近苯环及对位氮原子上。     

恒电压法制备掺杂聚苯胺薄膜

在不同的酸溶液中加入定量苯胺单体,利用电化学恒压法制备了导电性能优良的聚苯胺薄膜,研究了以不同浓度(0.5、1、1.5、2mol/L)的盐酸、高氯酸和对甲苯磺酸为电解质溶液,苯胺在ITO导电玻璃上的聚合电压和颜色变化,并用FT IR、循环伏安和SEM研究了聚合物的结构及性能。研究表明,在不同酸掺杂下薄膜的颜色依次为黄绿色、绿色、深绿色、天蓝色和深蓝色,这是由于不同掺杂酸对阴离子大小的不同导致其分子链上电荷离域不同,从而使得聚合物的掺杂程度不同而发生不同的红移;随着使用电压的增大,溶液中导电能力增强,聚苯胺薄膜的颜色加深;随着同种酸浓度的增加,质子酸的酸性越强,苯胺的聚合电位就越低。     

不同酸溶液中恒电压法制备聚苯胺薄膜

在不同的酸溶液中加入定量苯胺单体,利用电化学恒压法制备了导电性能优良的聚苯胺薄膜,研究了以不同浓度(0.5、1、1.5、2mol/L)的盐酸、高氯酸和对甲苯磺酸为电解质溶液,苯胺在ITO导电玻璃上的聚合电压和颜色变化,并用FT IR、循环伏安和SEM研究了聚合物的结构及性能。研究表明,在不同酸掺杂下薄膜的颜色依次为黄绿色、绿色、深绿色、天蓝色和深蓝色,这是由于不同掺杂酸对阴离子大小的不同导致其分子链上电荷离域不同,从而使得聚合物的掺杂程度不同而发生不同的红移;随着使用电压的增大,溶液中导电能力增强,聚苯胺薄膜的颜色加深;随着同种酸浓度的增加,质子酸的酸性越强,苯胺的聚合电位就越低。     

掺杂聚苯胺溶致液晶相的产生和表征

聚苯胺（PAN）具有共轭结构,从理论上满足形成液晶相的基本条件［1,2］．但由于聚苯胺难溶、难熔,长期以来对于聚苯胺溶液（尤其是浓溶液）或熔体的研究甚少．近年来,人们采用具有“增塑作用”的大分子功能质子酸对聚苯胺进行掺杂,获得可溶于多种有机溶剂中的掺杂态聚苯胺［3～5］．然而,聚苯胺溶液的结构与性能的特点及能否产生溶致液晶相等问题目前尚未见报道．为此,我们研究了十二烷基苯磺酸（DBSA）掺杂聚苯胺在有机溶剂中形成液晶相的条件,探讨了不同掺杂方法对PAN－DBSA的溶解性及形成液晶棺的影响;采用差式扫描量热分…     

掺杂态聚苯胺的共振拉曼光谱研究

观测了聚苯胺(PAn)在不同状态(掺杂、反掺杂、碱式、氧化、还原)下的拉曼光谱.根据其光谱特性,结合其它实验结果,提出了掺杂态PAn分子链包含电荷分布不等的三种苦环和二种氮原子的四单元苯醌变体模型,指出质子酸掺杂系分子内氧化还原反应,讨论了PAn氧化程度对掺杂效率的影响.     

复合酸掺杂导电聚苯胺的性能研究

以苯胺为单体、过硫酸胺为氧化剂,由化学氧化聚合法在磺基水杨酸和硫酸的复合酸的水溶液中合成导电聚苯胺,并通过压片法、激光粒度分析、扫描电镜、差热分析及红外光谱对掺杂态聚苯胺的电导率、表面形貌及结构进行了研究.结果表明,复合酸掺杂聚苯胺的热稳定性比仅用硫酸掺杂聚苯胺的有了很大的提高;所得导电聚苯胺的粒度分布比较均匀(平均粒径约15.4μm);复合酸掺杂使聚苯胺分子链上的电荷呈离域化,掺杂程度提高.     

化学计量学方法在动力学过程分析中的应用

提出了一种公因子分析的新方法。通过这一方法，对一个动力学体系，我们能够从两个不同的波长范围或反应时间范围的数据阵中获得共同组分的数目和它们的光谱或浓度曲线。将这一方法结合正交投影（OPR）技术，成功地应用于聚苯胺掺杂质子酸反应体系数据阵的解析，获得了这一过程中聚苯胺本征态及掺杂后两个新生结构的光谱和浓度变化曲线。基于解析结果可以推断：聚苯胺质子酸掺杂可能生成PANHn^n （α）、PANHn^a (β）两个不同结构的产物，他们间可相互转化。     

导电聚苯胺的合成、结构、性能和应用

概述了中国科学院长春应用化学研究所对导电聚苯胺合成、结构、性能和应用的研究.从合成可溶性的聚苯胺入手,阐明了聚苯胺的若干基本化学和结构问题,提出并证明了掺杂态聚苯胺的结构模型和掺杂机理;除了质子酸掺杂外,发现了聚苯胺的碘氧化掺杂、光助氧化掺杂和K+注入还原掺杂;开发了分别以环氧树脂和聚氨酯为载体的聚苯胺防腐涂料;运用掺杂剂诱导的溶解性,通过合成带聚乙二醇链的膦酸掺杂剂,实现了导电态聚苯胺的水体系加工.其中的聚苯胺树脂及防腐涂料的生产技术,已经完成中试,正在走向产业化.     

聚苯胺热掺杂十二烷基苯磺酸的反应过程及其结构

与传统的质子酸掺杂相比，采用具有功能性的两亲大分子对聚苯胺（PAN）掺杂，可以使产物的加工性和稳定性大大提高［1～3]．十二烷基苯磺酸（DBSA）是研究得比较多的掺杂酸之一，其掺杂过程一般都采用辅助溶剂，由此而引起PAN与DBSA结合程度低、掺杂效率低、溶剂需后处理?..     

聚苯胺在有机溶剂中掺杂质子酸的In-site UV-Vis光谱及其因子分析法解谱

对聚苯胺在有机溶剂中掺杂质子酸的反应进行了in-situ UV-Vis光谱跟踪,用因子分析法对掺杂反应机理进行了研究.结果表明,聚苯胺在有机溶剂中掺杂质子酸的过程可能存在着两个并行反应:一个是掺杂与脱掺杂的动态平衡过程,在实验条件下反应的平衡常数约为k=5.16(24℃);另一个反应为副反应,生成的产物结构介于本征态与平衡掺杂态之间,很可能是反应过程中形成的包含不同掺杂形态的混合体.     

苯胺乳液聚合条件的研究

以（ＮＨ４）２Ｓ２Ｏ８为氧化剂、在非极性溶剂－功能质子酸－水三相体系中,采用乳液聚合方法合成聚苯胺乳液和粉末。对乳液聚合与化学氧化溶液聚合合成的聚苯胺性能进行了比较,研究了掺杂酸、氧化剂、反应时间、温度和水相浓度等聚合条件对聚苯胺导电性、溶解性、乳液粘度等性能的影响。结果表明,乳液聚合产率大于８０％,聚苯胺电导率大于１Ｓ／ｃｍ,在有机溶剂中的溶解性与用化学氧化合成的聚苯胺相比有明显提高。     

Preparation and Properties of Water-based Conducting Polyaniline

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Synthesis and characterization of polyaniline doped with organic acids

Spectroscopic [UV–visible and Fourier transform IR (FTIR)] and thermal properties of chemically synthesized polyanilines are found to be affected by varying the protonation media (acetic, citric, oxalic, and tartaric acid). The optical spectra show the presence of a greater fraction of fully oxidized insulating pernigraniline phase in polyaniline doped with acetic acid. In contrast, the selectivity in the formation of the conducting phase is higher in oxalic acid as a protonic acid media. The FTIR spectra of these polymers reveal a higher ratio of the relative intensities of the quinoid to benzenoid ring modes in acetic acid doped polyaniline. Scanning electron micrographs revealed a sponge‐like structure derived from the aggregation of the small granules in acetic acid and oxalic acid doped polyaniline. A three‐step decomposition pattern is observed in all the polymers, regardless of the protonic acid used for the doping. The second step loss related to the loss of dopant is found to be higher in the oxalic acid doped polymer. In accordance with these results the conductivity is also found to be higher in oxalic acid doped material. The temperature dependent conductivity measurements show the thermal activated behavior in all the polymers. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2043–2049, 2004     

Preparation of polyaniline‐sulfate salt ­by emulsion and aqueous ­polymerization pathway without using ­protonic acid

Aniline was polymerized directly into polyaniline‐sulfate salt without using protonic acid in this work. Polyaniline‐sulfate salt was prepared by emulsion and aqueous polymerization pathways. The dopant i.e. sulfate ion in polyaniline‐sulfate salt was generated from ammonium persulfate which was used for oxidizing aniline. Ammonium persulfate acts both as oxidizing agent as well as protonating agent in the polymerization process of aniline to polyaniline salt. The efficiency of oxidizing and protonating power of ammonium persulfate is increased by the use of surfactant. The activity of ammonium persulfate is further increased by the use of sulfuric acid as protonic acid. It may be necessary to consider the effect of sulfate ion which is generated during the oxidation process of aniline in the chemical polymerization of aniline to polyaniline salt by ammonium persulfate either aqueous or emulsion polymerization pathway in the presence of protonic acid/functionalized protonic acid. Copyright © 2001 John Wiley & Sons, Ltd.     

Composition and spectral studies of polyaniline salts

Five different polyaniline salts have been prepared by chemical polymerization of aniline in aqueous solution of different acids. The polyaniline base was obtained from the corresponding polyaniline salt by dedoping using aqueous ammonium hydroxide solution. Electron paramagnetic, electronic absorption, infrared spectral and conductivity measurements have been performed on the polyaniline salts and polyaniline bases. This composition and the extent of dopant in polyaniline salt systems have been determined. There is no definite correlation between the conductivity and the stoichiometric ratio between the polyaniline base and the acid, and also the spin concentration.     

Synthesis and Characterization of Conducting Polyaniline Doped with Polymeric Acids

Conducting polyaniline doped with polymeric acids was synthesized by a in situ chemical polymerization method. The synthesized polymers were characterized by using UV‐Visible, FT‐IR spectroscopy and SEM analysis. Thermal stability of these polymers was evaluated by using TGA/DSC analysis. Among the three polymeric acids used for doping purpose, poly(vinyl sulphonic acid) doped polyaniline is found to be more conducting than those doped with other acids. From the temperature dependent conductivity measurements, an increase in conductivity with increase in temperature was observed.     

Preparation and properties of polyaniline codoped with ionic liquid and dodecyl benzene sulfonic acid or hydrochloric acid

Three nanosized polyaniline (PAn) powders doped with ionic liquid and dodecyl benzene sulfonic acid (DBSA) or hydrochloric acid have been prepared for the first time in an ionic liquid-water emulsion system. The oil-phase ionic liquid is used as both a monomer solvent and doped counterion. The effects of different counterions on the properties (molecular weight, electrical conductivity, glass transition temperature, electrochemical activity) of PAn are investigated. PAn codoped with 1-butyl-3-methylimidazolium hexafluorophosphate ionic liquid and DBSA shows the highest molecular weight (81 104 g mol^?1), the highest electrical conductivity (1.85 S cm^?1), the lowest glass transition temperature (181°C) and the highest redox reaction current density; PAn doped with an ionic liquid only exhibits the lowest conductivity (0.0018 S cm^?1) and a lower redox reaction current density. PAn codoped with ionic liquid and HCl shows higher conductivity. They also exhibit good electrochemical stability and charge-discharge performance. These indicate that codoping of different counterions under acidic conditions could improve the degree of oxidation and doping ratio of PAn and could result in high electrical conductivity and good electrochemical properties.     

Thermal transporting properties of electrically conductive polyaniline films as organic thermoelectric materials

Thermal transporting properties of electrically conductive polyaniline films were first investigated in wide range of temperatures above room temperature as organic thermoelectric materials. Thermal conductivities of various protonic acid-doped polyaniline films were measured by combination of a laser flash method and a differential scanning calorimeter in relation with electrical conductivity and a kind of dopant. The thermal conductivities thus measured are in the range of conventional organic polymers, indicating that the doped polyaniline films have extremely low thermal conductivities among electrically conductive materials, and have correlation with neither electrical conductivity, nor a kind of dopant. Consequently the polyaniline film, which shows very high electrical conductivity, has comparable thermoelectric figure-of-merit (ZT) with feasible inorganic thermoelectric materials such as iron silicide. This revised version was published online in August 2006 with corrections to the Cover Date.     

The role of molecular recognition in charge transport properties of doped polyaniline

Molecular recognition plays a significant role in the counterion-induced processibility, morphological features, and physical properties of doped polyaniline (PANI). The interaction of the counterion and solvent controls the chain conformation and, as a result, the formation of extended and localized electronic states; hence, it holds the key for tuning a wide range of electrical and optical properties of doped PANI. The combined effects of counterion, solvent, and processing conditions tune the metal-insulator transition, temperature dependence of conductivity, magnetoresistance, and so forth in doped PANI. The typical examples are shown in the case of PANI doped by camphor sulfonic acid, 2-acrylamido-2-methyl-1-propane sulfonic acid, and dodecylbenzoyl sulfonic acid.     

不同质子酸掺杂对银/聚苯胺纳米复合材料结构和导电性的影响

利用紫外光作为辅助条件,在反胶束体系中采用一步双原位法合成了硝酸(HNO3)、对甲基苯磺酸(TSA)和5-磺基水杨酸(SSA)掺杂的银/聚苯胺(Ag/PANI)纳米复合材料.通过对复合材料进行红外光谱(FTIR)、紫外光谱(UV-Vis)、扫描电镜(SEM)、X射线衍射(XRD)和导电性能的测试,研究了不同质子酸对Ag/PANI纳米复合材料结构、形貌和导电性能的影响.测试结果表明,3种酸掺杂制备的Ag/PANI纳米复合材料均为聚苯胺包覆银粒子的核-壳结构.不同的质子酸掺杂会对Ag/PANI纳米复合材料的电性能有重要影响.在3种酸掺杂的复合材料中,TSA掺杂的复合材料的电导率最佳,为215.14 S·cm-1.